Such a functional system can be constituted by an automotive vehicle secondary brake.
Secondary brake devices, that is to say parking brake devices, are known wherein activation is effected by electric actuators whose operation is governed by a user by way of a control member making it possible to drive the powering of the actuator.
The control member is constituted in such devices in particular by a switch making it possible to power or otherwise the actuator, that is to say in fact to bring about complete application or release of the secondary brake of the vehicle.
Systems of this type also comprise electronic means for managing the powering of the actuator as a function of cues emanating from sensors for example sensing the rate of rotation of the wheels of the vehicle, such as those used in wheel anti-lock systems.
However, such means have a number of drawbacks, especially as regards their cost, their operation and their manipulation by a user.
Indeed, one is aware that managing the holding of a vehicle stationary on a slope is relatively simple to manage with such an interface, by for example powering the actuator under full voltage.
However, the cue delivered to the device by the user via such an interface, is of the all or nothing type, whereas by using a traditional brake lever for tensioning the cables for applying the secondary brake, the user manages the tension of the cable and its rate of tensioning and regulates the latter as a function of the deceleration of the vehicle.
It is appreciated that for various reasons it is desirable to preserve such functional capabilities.
The objective of the invention is therefore to solve these problems at minimum cost.
To this end, the subject of the invention is a process for controlling an electric actuator for activating a functional system, especially an automotive vehicle secondary brake, of the type comprising a control member actuatable by a user so as to govern the powering of the actuator, characterized in that it comprises the following steps:
a) the movements of the control member are estimated, in terms of direction and amplitude, along a travel thereof between extreme positions of control of the actuator, and PA1 b) these movements are analysed so as to derive therefrom a cue for controlling means for powering the actuator so as to supply to the latter a quantity of current corresponding to the movement of the control member, as determined on the basis of a predetermined correspondence law and of means for aggregating the successive movements of the actuator during its various controls, and updated after each new control thereof, so as to slave the position of the actuator to the position of the control member. PA1 a) means for estimating the movements of the control member, in terms of direction and amplitude, along a travel thereof between extreme positions of control of the actuator, and PA1 b) means for analysing these movements so as to derive therefrom a cue for controlling means for powering the actuator so as to supply the latter with a quantity of current corresponding to the movement of the control member, as determined by these means of analysis on the basis of a predetermined correspondence law stored in the latter means and of means for aggregating the successive movements of the actuator during its various controls, and updated after each new control of the actuator by these means of analysis, so as to slave the position of the actuator to the position of the control member.
According to another aspect, the subject of the invention is also a device for controlling an electric actuator for activating a functional system, especially an automotive vehicle secondary brake, of the type comprising a control member actuatable by a user so as to govern the powering of the actuator, characterized in that it comprises:
The invention will be better understood with the aid of the description which follows, given merely by way of example while referring to the appended drawings in which: